FUGLY !!!
'
They look like some kinda rusty ol' farm yard $4!7
The anode/cathode format is shrinking !
But still OFFICIALLY all 6V6 s !
Possibly an answer to ruggedness & miniaturization in portable radio applications ?
No microphonies with these tin-cans ...
... & you can let the kids play skittles with 'em !
From my collection.
Si.
t.S.E.c
.
'
They look like some kinda rusty ol' farm yard $4!7
The anode/cathode format is shrinking !
But still OFFICIALLY all 6V6 s !
Possibly an answer to ruggedness & miniaturization in portable radio applications ?
No microphonies with these tin-cans ...
... & you can let the kids play skittles with 'em !
From my collection.
Si.
t.S.E.c
.
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TOP GUN ! ... Boris.
.
Thought I'd have a bit of a nose around & see what C L toobz I could find.
Came across a 'near' Ruskie equivalent to the 6V6 / 6AQ5 ...
... EXCEPT it comes with a DIFFERENT BASE ... 9-Pin !
HOLY COW ! ... These Soviet special 'EV' grade by Svetlana, with Gold & Platinum whotnots ROCK !
You can just tell they have put a lot of effort into making these babys !
Makes my Canadian made 6AQ5s in the green-boxes, look like they were assembled my monkeys !
My first job in electronics back in late '70s Punk Rock London, was making toobz !
You can just SMELL a good tube a mile off !
I bet these 'EV' Ruskie 9-pins would just sing like divas in 'The Mr. Salas Signature Spec. Ed.'
Nice price as well Boris !
Si.
t.S.E.c
.
.
Thought I'd have a bit of a nose around & see what C
L toobz I could find. Came across a 'near' Ruskie equivalent to the 6V6 / 6AQ5 ...
... EXCEPT it comes with a DIFFERENT BASE ... 9-Pin !
HOLY COW ! ... These Soviet special 'EV' grade by Svetlana, with Gold & Platinum whotnots ROCK !
You can just tell they have put a lot of effort into making these babys !
Makes my Canadian made 6AQ5s in the green-boxes, look like they were assembled my monkeys !
My first job in electronics back in late '70s Punk Rock London, was making toobz !
You can just SMELL a good tube a mile off !
I bet these 'EV' Ruskie 9-pins would just sing like divas in 'The Mr. Salas Signature Spec. Ed.'
Nice price as well Boris !
Si.
t.S.E.c
.
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Indeed they are. I built this with them. At the time they were $1 each. The chassis was salvage.
The "Stupendous" 6P1P 4PP amplifier!
The "Stupendous" 6P1P 4PP amplifier!
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I like it for the money, and the linearity is good. They are biased at 10.8W Pd each.
Makes about 15W in class A, and it's one of the best sounding amplifiers I've ever heard. The other being my 6P45S in triode, but that one makes almost 120W.
Smoke On The Water ... & ... matching Ruskie bottles ?
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" 6П1П is exactly naked original 6V6 packed in a 9-pin envelope "
Hi Wavebourn
Hey thanks for that.
It sure did look darn familiar to me as well.
Only problem with seeing inside 'most' 6V6G/GT is the smoked glass !
I'm sure I'm the last dunce to know this, but WHY are some tubes smoked inside ?
Some of the ol' glass germanium transistors were light sensitive & got painted.
It's not the case with toobz ... or is it ? ... Nar surely not.
- - - - - - -
Hi kodabmx
It looks like you have a ton of those 6П1П toobz there. 
I think the Svetlana factory was known for consistent product.
The EVs getting extra effort as well I believe.
But how easy was it for you to get the matching required for your amp ?
Did you just buy a couple of dozen or so & see what you got or what ?
I'm just curious to guess how easy it would be to get 4 of these close for a balanced preamp ?
Mmm ...
Russian octal 6V6 pairs are available, but I haven't seen that quads are so easily.
Those oDd 9-Pins sure are an attractive price, especially in bulk.
Si.
t.S.E.c
.
.
" 6П1П is exactly naked original 6V6 packed in a 9-pin envelope "
Hi Wavebourn
Hey thanks for that.
It sure did look darn familiar to me as well.
Only problem with seeing inside 'most' 6V6G/GT is the smoked
glass !I'm sure I'm the last dunce to know this, but WHY are some tubes smoked inside ?
Some of the ol' glass germanium transistors were light sensitive & got painted.
It's not the case with toobz ... or is it ? ... Nar surely not.
- - - - - - -
Hi kodabmx
It looks like you have a ton of those 6П1П toobz there.
I think the Svetlana factory was known for consistent product.
The EVs getting extra effort as well I believe.
But how easy was it for you to get the matching required for your amp ?
Did you just buy a couple of dozen or so & see what you got or what ?
I'm just curious to guess how easy it would be to get 4 of these close for a balanced preamp ?
Mmm ...
Russian octal 6V6 pairs are available, but I haven't seen that quads are so easily.
Those oDd 9-Pins sure are an attractive price, especially in bulk.
Si.
t.S.E.c
.
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Each tube is biased by it's own CCS in the cathode leg. They are set to 40mA, and the B+ is about 300V.
If the voltage across the CCS is roughly the same, I call it good enough. All 16 tubes are within 1V of each other. There was a tube that failed early. It was 5V lower in bias voltage than the rest but the only effect was less power and earlier distortion.
If the voltage across the CCS is roughly the same, I call it good enough. All 16 tubes are within 1V of each other. There was a tube that failed early. It was 5V lower in bias voltage than the rest but the only effect was less power and earlier distortion.
A high pass filter is created with the power amp's input impedance, it has (-3dB) fc=1/2πRC.
Try not to have less than 150ms RC time in the resulting filter with the various amps you may use. In other words don't cut off above 2.5Hz. That's to avoid early phase turn in the lows. Even when the power amp is tube and its output trafo has shift in the lows, no point to add even more.
Because it was mainly used with a 120k input KT88 amp of my design, they had 1.95Hz Fc (188ms) when coupled with 0.68uF. If you have a 100k input amp don't go under 0.68uF. If you got a 150k amp 0.47uF behaves alike. But if you got a 20k amp, then 3.3uF behaves alike. And so on and so forth.
Try not to have less than 150ms RC time in the resulting filter with the various amps you may use. In other words don't cut off above 2.5Hz. That's to avoid early phase turn in the lows. Even when the power amp is tube and its output trafo has shift in the lows, no point to add even more.
Because it was mainly used with a 120k input KT88 amp of my design, they had 1.95Hz Fc (188ms) when coupled with 0.68uF. If you have a 100k input amp don't go under 0.68uF. If you got a 150k amp 0.47uF behaves alike. But if you got a 20k amp, then 3.3uF behaves alike. And so on and so forth.
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Thank you Salas. I'd forgot about that formula.
I've just built your 6V6 preamp and I think it's great. It's a keeper for sure. No noise whatsoever exept some mechanical buzzing from the mains transformer that I have to look into. The plate resistors is a bit too hot for my liking so those need changing to wirewounds.
I've just built your 6V6 preamp and I think it's great. It's a keeper for sure. No noise whatsoever exept some mechanical buzzing from the mains transformer that I have to look into. The plate resistors is a bit too hot for my liking so those need changing to wirewounds.
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Yes it is the gain version. It drives my 4P1L SPUD headphone amplifier. Not that SPUD anymore with a preamp, but I have come to the conclusion that several gain stages aren't necessarily a bad thing. I might add that I also own a 26 preamp so I think I can make a fair judgement of the quality of your 6V6 preamp. 300B monoblocks are in the planning stage.
Can somebody list worthy 6V6 candidates with some sound descriptions to try out with this preamp? Please use words like fullness, transparency, darkness, lightness, extention, bass, midrange, treble, 3 dimentionality, dynamics and so on. The things I've read on the net almost always seems related to guitar amps, and it doesn't really tell me anything about the use in a preamp.